var win = document.getElementsByTagName('html')[0];
var w = document.documentElement.clientWidth;
			//当前屏幕可视宽度
	win.style.fontSize = w*0.0625 + 'px';
	
	window.onresize = function(){
		var w = document.documentElement.clientWidth;
		win.style.fontSize = w*0.0625 + 'px';

	}